Nor do I teach because I think I know answers, or because I have knowledge I feel compelled to share. Sometimes I am amazed that my students actually take notes on what I say in class!
Why, then, do I teach?
I teach because I like the pace of the academic calendar. June, July, and August offer an opportunity for reflection, research and writing.
I teach because teaching is a profession built on change. When the material is the same, I change —— and, more important, my students change.
I teach because I like the freedom to make my own mistakes, to learn my own lessons, to stimulate myself and my students. As a teacher, I'm my own boss. If I want my freshmen to learn to write by creating their own textbook, who is to say I can't? Such courses may be huge failures, but we can all learn from failures.
I teach because I like to ask questions that students must struggle to answer. The world is full of right answers to bad questions. While teaching, I sometimes find good questions.
I teach because I enjoy finding ways of getting myself and my students out of the ivory tower and into the real world. I once taught a course called "Self-Reliance in a Technological Society." My 15 students read Emerson, Thoreau, and Huxley. They kept diaries. They wrote term papers.
But we also set up a corporation, borrowed money, purchased a run-down house and practiced self-reliance by renovating it. At the end of the semester, we would the house, repaid our loan偿还贷款, paid or taxes, and distributed the profits among the group.
So teaching gives me pace, and variety, and challenge, and the opportunity to keep on learning.

convince
vt. make (sb.) feel certain; cause (sb.) to realize
compel
vt. force (sb. or sth. to do sth.)
pace
n. rate or speed of development, or in walking, etc. 速度；步速
calendar solar calendar lunar calendar
n. 日程表，日历
opportunity
n. favourable occasion or chance
reflection reflect v 反射，反思
n. careful thinking; consideration 深思；考虑
reflect vi.
stimulate
vt. encourage; excite 刺激；激励
freshman
n. student in his first year at a college or university
failure
n. a person, attempt, or thing that fails; lack of success
ivory
n. 象牙
ivory tower
n. place or condition of retreat from the world of action into a world of ideas and dreams 象牙塔
self-reliance
n. ability to do things and make decisions by oneself 依靠自己；自力更生
reliance
n. trust, confidence; dependence 信赖；信心；依靠
technological
a. of or related to technology 技术的
corporation
n. (AmE) 有限公司
run-down
a. old and broken or in bad condition残破不堪
renovate revolution革新
vt. restore (old buildings, oil paintings, etc.) to a former, better state 修复，修整
semester
n. (AmE) either of the two periods into which a school year is divided; term 学期
repay
vt. pay back (money, etc.)
loan
n. sth. lent, esp. a sum of money 借出的东西；贷款
distribute contribute贡献、有助于、导致=cause attribute把。。归于
vt. divide among several or many; give or send out 分发；分送
distribution n.
variety a variety of
n. difference in quality, type or character; a number of or a collection of different things 变化，多样化；种种
challenge challenging 有挑战性的
n. the quality of demanding competitive action, interest, or though 挑战